The present invention relates generally to gas lasers, and more particularly to a multiple discharge gas laser apparatus capable of simultaneously providing several intense light beams suitable for marking objects by ablation of the surface thereof, for secure communications, and for remote sensing, among other applications.
Systems where multiple laser beams are required employ a plurality of independent laser sources which is both expensive and requires adjustment of numerous optical devices in order to locate the laser beams in the position or area of their utilization. For example, in "Laser Marking Apparatus," U.S. Pat. No. 4,652,722, issued to Joseph J. Stone and Leroy V. Sutter, Jr. on Mar. 24, 1987, the inventors describe a laser marking system which employs a plurality of individual lasers or a monolithic unit having a plurality of beams which are directed by fixed mirrors onto the surface to be marked. The surface to be marked is positioned on a conventional conveyor or other device suitable for linear motion across the laser beam. Each laser defines a collimated energy source which is focused, by an exit lens which has it focal plane approximately at the object to be marked, into a dot of chosen size. The incident angle of each laser source on the focusing lens is adjusted to provide a plurality of closely and focused dots which define a vertical column of light dots from which an alpha-numeric matrix can be obtained by modulation of the dots as the article moves past the exit lens. After initial adjustment, no further movement of the mirrors is required.
Accordingly, an object of the present invention is to provide a multiple discharge gas laser which has reduced numbers of electrodes over that required from the use of distinct lasing systems.
Another object of my invention is to provide a multiple discharge gas laser apparatus having laser beams which are substantially parallel in the far field except for mode structure.
Yet another object of my invention is to provide a multiple discharge gas laser apparatus suitable for marking objects by ablation of the surface thereof.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.